That said, I'm not sure that these details are that important - perl programmers are a pragmatic bunch, so we just use what we have available, and install what we don't but we need. :-)

Yes, but the problem is that it is harder and more annoying to install a module or application if the dependencies are not listed properly. I for one have never listed strict and warnings (among other core modules) in the PREREQ_PM section of my Makefile.PL. I never imagined that someone would dare distribute perl without these modules! (Now, I hope that at least they include ExtUtils::MakeMaker...)